The invention relates to a fuel tank for motor vehicles, with a filler neck, on which a vent line and a receptacle for a pump nozzle are provided.
In a known fuel tank of the species cited hereinabove (German Offenlegungsschrift No. 2,208,189), a receptacle for a pump nozzle is located upstream of the opening of a vent tube, viewed in the direction of reverse flow. It has been found in practice that this arrangement does not sufficiently ensure that an individual filling the vehicle with fuel will not be spattered with fuel. The volume at which the fuel is introduced into the tank (60 L/minute) produces compression, especially just before the pump nozzle shuts off, in other words, a reverse flow of the air in the tank through the vent line. This medium, flowing in the reverse direction, entrains fuel particles, even carrying them past the receptacle, producing the above-mentioned nuisance.
It is thus an object of the invention to make provisions in the filler neck of a fuel tank which will avoid the above-mentioned disadvantages.
This object is achieved according to a preferred embodiment of the invention by virtue of the fact that a receptacle surrounds the pump nozzle, at least for a portion of its length, and nearly comes in contact with it, the receptacle being associated with an insert which delimits a space on all sides and is closed on the side facing the tank, but has openings on the opposite side, and by the fact that a vent line terminates in the space. It is advantageous in this connection if the receptacle surrounds the pump nozzle with a collar, and extends between an outer bulkhead and an inner bulkhead of the insert. The receptacle has a conical part between the collar and the outer bulkhead. The openings are provided in the conical part of the receptacle. The vent line runs in a known fashion inside the filler neck and is connected to the inner bulkhead. It is also possible, in accordance with a preferred embodiment, to connect a vent line, which is known of itself and runs outside the filler neck, in an area between the bulkheads, against this filler neck. The outer bulkhead and the receptacle are connected integrally with one another whereby the collar projects into an opening of the separate, inner bulkhead. It is also possible, in accordance with a further embodiment, to connect the bulkheads of the insert integrally with one another and to mount them to the tube segment by flanges.
Among particular advantages achieved with the invention is the fact that, by disposing the vent line in the chamber which is cut off from the tank, entrainment of fuel particles is ruled out for all practical purposes so that the person filling the tank with fuel is protected from a spray of fuel. This is especially important in view of the trend for drivers wearing ordinary clothing to fill their vehicles themselves with fuel. A further advantage is that the parts of the insert are simple in design and can easily be inserted in the filler neck.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.